OTHER THAN VLV SIZES ,AND THE HOT PLUGS IN THE COMBUSTION CHAMBER, YOU WON,T NOTICE ANY DIFF, AND IT WILL RUN JUST FINE, THE VLVS IN THE TURBO ARE OF A DIFF MATERIAL SO ARE THE HOT PLUGS , TO WITHSATND THE HIGHER THAN NORMAL EXHAUST TEMPS , SO DON,T GO FLOGGING THE DAYLITES OUT OF IT AND YOU WILL BE FINE , THE TURBO HEADS ARE GETTING HARD TO FIND , JERRY